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-rw-r--r--drivers/iio/adc/at91-sama5d2_adc.c142
1 files changed, 72 insertions, 70 deletions
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index 77a7169a2759..60f7aef906e0 100644
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -728,7 +728,6 @@ static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
struct iio_dev *indio = iio_trigger_get_drvdata(trig);
struct at91_adc_state *st = iio_priv(indio);
u32 status = at91_adc_readl(st, AT91_SAMA5D2_TRGR);
- u8 bit;
/* clear TRGMOD */
status &= ~AT91_SAMA5D2_TRGR_TRGMOD_MASK;
@@ -739,48 +738,6 @@ static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
/* set/unset hw trigger */
at91_adc_writel(st, AT91_SAMA5D2_TRGR, status);
- for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) {
- struct iio_chan_spec const *chan = at91_adc_chan_get(indio, bit);
- u32 cor;
-
- if (!chan)
- continue;
- /* these channel types cannot be handled by this trigger */
- if (chan->type == IIO_POSITIONRELATIVE ||
- chan->type == IIO_PRESSURE)
- continue;
-
- if (state) {
- cor = at91_adc_readl(st, AT91_SAMA5D2_COR);
-
- if (chan->differential)
- cor |= (BIT(chan->channel) |
- BIT(chan->channel2)) <<
- AT91_SAMA5D2_COR_DIFF_OFFSET;
- else
- cor &= ~(BIT(chan->channel) <<
- AT91_SAMA5D2_COR_DIFF_OFFSET);
-
- at91_adc_writel(st, AT91_SAMA5D2_COR, cor);
- }
-
- if (state)
- at91_adc_writel(st, AT91_SAMA5D2_CHER,
- BIT(chan->channel));
- else
- at91_adc_writel(st, AT91_SAMA5D2_CHDR,
- BIT(chan->channel));
- }
-
- /* Nothing to do if using DMA */
- if (st->dma_st.dma_chan)
- return 0;
-
- if (state)
- at91_adc_writel(st, AT91_SAMA5D2_IER, AT91_SAMA5D2_IER_DRDY);
- else
- at91_adc_writel(st, AT91_SAMA5D2_IDR, AT91_SAMA5D2_IER_DRDY);
-
return 0;
}
@@ -905,9 +862,22 @@ static int at91_adc_dma_start(struct iio_dev *indio_dev)
return 0;
}
+static bool at91_adc_buffer_check_use_irq(struct iio_dev *indio,
+ struct at91_adc_state *st)
+{
+ /* if using DMA, we do not use our own IRQ (we use DMA-controller) */
+ if (st->dma_st.dma_chan)
+ return false;
+ /* if the trigger is not ours, then it has its own IRQ */
+ if (iio_trigger_validate_own_device(indio->trig, indio))
+ return false;
+ return true;
+}
+
static int at91_adc_buffer_postenable(struct iio_dev *indio_dev)
{
int ret;
+ u8 bit;
struct at91_adc_state *st = iio_priv(indio_dev);
/* check if we are enabling triggered buffer or the touchscreen */
@@ -928,6 +898,36 @@ static int at91_adc_buffer_postenable(struct iio_dev *indio_dev)
return ret;
}
+ for_each_set_bit(bit, indio_dev->active_scan_mask,
+ indio_dev->num_channels) {
+ struct iio_chan_spec const *chan =
+ at91_adc_chan_get(indio_dev, bit);
+ u32 cor;
+
+ if (!chan)
+ continue;
+ /* these channel types cannot be handled by this trigger */
+ if (chan->type == IIO_POSITIONRELATIVE ||
+ chan->type == IIO_PRESSURE)
+ continue;
+
+ cor = at91_adc_readl(st, AT91_SAMA5D2_COR);
+
+ if (chan->differential)
+ cor |= (BIT(chan->channel) | BIT(chan->channel2)) <<
+ AT91_SAMA5D2_COR_DIFF_OFFSET;
+ else
+ cor &= ~(BIT(chan->channel) <<
+ AT91_SAMA5D2_COR_DIFF_OFFSET);
+
+ at91_adc_writel(st, AT91_SAMA5D2_COR, cor);
+
+ at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel));
+ }
+
+ if (at91_adc_buffer_check_use_irq(indio_dev, st))
+ at91_adc_writel(st, AT91_SAMA5D2_IER, AT91_SAMA5D2_IER_DRDY);
+
return iio_triggered_buffer_postenable(indio_dev);
}
@@ -948,21 +948,11 @@ static int at91_adc_buffer_predisable(struct iio_dev *indio_dev)
if (!(indio_dev->currentmode & INDIO_ALL_TRIGGERED_MODES))
return -EINVAL;
- /* continue with the triggered buffer */
- ret = iio_triggered_buffer_predisable(indio_dev);
- if (ret < 0)
- dev_err(&indio_dev->dev, "buffer predisable failed\n");
-
- if (!st->dma_st.dma_chan)
- return ret;
-
- /* if we are using DMA we must clear registers and end DMA */
- dmaengine_terminate_sync(st->dma_st.dma_chan);
-
/*
- * For each enabled channel we must read the last converted value
+ * For each enable channel we must disable it in hardware.
+ * In the case of DMA, we must read the last converted value
* to clear EOC status and not get a possible interrupt later.
- * This value is being read by DMA from LCDR anyway
+ * This value is being read by DMA from LCDR anyway, so it's not lost.
*/
for_each_set_bit(bit, indio_dev->active_scan_mask,
indio_dev->num_channels) {
@@ -975,12 +965,28 @@ static int at91_adc_buffer_predisable(struct iio_dev *indio_dev)
if (chan->type == IIO_POSITIONRELATIVE ||
chan->type == IIO_PRESSURE)
continue;
+
+ at91_adc_writel(st, AT91_SAMA5D2_CHDR, BIT(chan->channel));
+
if (st->dma_st.dma_chan)
at91_adc_readl(st, chan->address);
}
+ if (at91_adc_buffer_check_use_irq(indio_dev, st))
+ at91_adc_writel(st, AT91_SAMA5D2_IDR, AT91_SAMA5D2_IER_DRDY);
+
/* read overflow register to clear possible overflow status */
at91_adc_readl(st, AT91_SAMA5D2_OVER);
+
+ /* continue with the triggered buffer */
+ ret = iio_triggered_buffer_predisable(indio_dev);
+ if (ret < 0)
+ dev_err(&indio_dev->dev, "buffer predisable failed\n");
+
+ /* if we are using DMA we must clear registers and end DMA */
+ if (st->dma_st.dma_chan)
+ dmaengine_terminate_sync(st->dma_st.dma_chan);
+
return ret;
}
@@ -1135,6 +1141,13 @@ static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
struct iio_dev *indio_dev = pf->indio_dev;
struct at91_adc_state *st = iio_priv(indio_dev);
+ /*
+ * If it's not our trigger, start a conversion now, as we are
+ * actually polling the trigger now.
+ */
+ if (iio_trigger_validate_own_device(indio_dev->trig, indio_dev))
+ at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_START);
+
if (st->dma_st.dma_chan)
at91_adc_trigger_handler_dma(indio_dev);
else
@@ -1147,20 +1160,9 @@ static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
static int at91_adc_buffer_init(struct iio_dev *indio)
{
- struct at91_adc_state *st = iio_priv(indio);
-
- if (st->selected_trig->hw_trig) {
- return devm_iio_triggered_buffer_setup(&indio->dev, indio,
- &iio_pollfunc_store_time,
- &at91_adc_trigger_handler, &at91_buffer_setup_ops);
- }
- /*
- * we need to prepare the buffer ops in case we will get
- * another buffer attached (like a callback buffer for the touchscreen)
- */
- indio->setup_ops = &at91_buffer_setup_ops;
-
- return 0;
+ return devm_iio_triggered_buffer_setup(&indio->dev, indio,
+ &iio_pollfunc_store_time,
+ &at91_adc_trigger_handler, &at91_buffer_setup_ops);
}
static unsigned at91_adc_startup_time(unsigned startup_time_min,